I know that this surprises a LOT of people who are learning about ADHD, but yes perfectionism is one of the coping mechanisms that ADHDers tend to develop. The problem with ADHDers is that we have a unique style of perfectionism that tends to magnify our differences and justify our walls of awful rather than dealing with them.
The ADHD Style of Perfectionism
So how can someone who is constantly unable to finish tasks and is very easily distracted become perfectionistic? There are a few branches of perfectionism in ADHD that tend to come together and tend to add to our "Wall of Awful".
ADHDers tend to have perfectionism that prevents the starting of tasks. Ever heard an artist say "I have to be in the right mood"? THAT is perfectionism that hits ADHDers! The stars must be aligned, everything must be perfectly set up, and if anything doesn't feel JUST right... NOPE. Not happening.